The mother-infant relationship has been characterized as one of the most important relationships affecting the health and development of the human species. When that relationship involves child abuse or neglect, it is associated with cognitive and academic delays, psychiatric illness, social impairment and delinquency. However, little is known about the neuroendocrine processes underlying this attachment relationship. The long-term objectives of this career development award are: 1. To explore the neurobiological basis of mother-infant attachment, including neuroanatomical and neuroendocrine correlates; 2. To explore whether a disruption in these processes may be associated with child neglect and failure-to-thrive; and 3. To better understand how insecure or disorganized attachment may contribute to impaired cognitive and emotional development in children. The aims of the research proposal are: 1. To identify functional neuroanatomical correlates of mother-infant attachment, measuring maternal functional MRI responses to infant facial cues; 2. To identify differences in mothers' infant-related stress responses, measuring sequential levels of blood oxytocin, cortisol and catecholamines; 3. To determine defferences in mother-infant contingency responses, using the Mirror Interaction Situation; and 4. To determine the degree of correlation between maternal and infant attachment classifications, using the Adult Attachment Interview on study entry, and the Strange Situation procedure 8 months later. Sixty right-handed first-time mothers will be enrolled in the study, along with their full-term infants, aged 8 months (+/- 1 month). The mother's attachment classification will be determined using the Adult Attachment Interview. Serum oxytocin, cortisol and catecholamine levels will be obtained sequentially from the mothers during a standardized period of mother-infant interaction, the Mirror Interaction Situation. During this time, infant facial expressions and patterns of mother-infant interaction will be videotaped and subsequently analysed. Blood-oxygen-level-dependent functional MRI (BOLD-fMRI) will then be used to measure maternal brain responses to infant facial cues, comparing her own infant with unknown infant facial images. Infant attachment will be assessed 8 months later using the Strange Situation procedure.